Dynamic NBTI characteristics of p-MOSFET with N-plasma SiON Gate Dielectric

In this paper, the dynamic negative bias temperature instability (DNBTI) characteristics of p-MOSFET with N-plasma SiON dielectric are studied. Under dynamic stress, the nearly consistent frequency dependent characteristics of threshold voltage shift (DeltaV
_th
) and interface trap density (DeltaN
_it
) were observed. The results show that the degradation and recovery of DNBTI are still dominated by the generation and passivation of the interfacial traps associated with Si-H bond breaking and released H species diffusion during stress phase and back diffusion of H and repassivation of broken equivSi bonds during passivation phase, which could be depicted by the so-called reaction-diffusion (R-D) model. Meanwhile, the reduced passivation effect with increased stress time was observed, which suggests that the generation and passivation of N
_it
seems to present a fatigue effect. These observed DNBTI characteristics may relate to the nitrogen trapping effect on the diffusion of H species in SiON dielectric layer